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Discussion Starter #1
I have read in a couple of places that there were two "qualities" of the 7.3l built - one used in pickup trucks, vans and SUV's and another built for heavier purposes. The first is supposedly good for +-200K miles, the second for about half a million. I can't find the original page. When I search on this, I find no such information. Do you know anything about it?
 

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I've been driving one since 1989. Had a 6.9 before that. Don't know of any heavier parts on the 7.3 as far as block, crank, etc goes but it could be. The turbo models did have some different parts such as pistons and rings. If properly cared for the pickup truck engines would go a half million. My current one has 322,000 on it. One mistake some made was trying to put a turbo on the non turbo engine without changing the pistons and rings. That was pretty much a guarantee for failure.
 

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As I recall the 94 turbo block was strenghtened, as well has heavier rods and I believe wrist pins. Probably other things as well. Don't know about the ones in heavier trucks. I do recall they used a different pump on some or maybe all. It's was a inline pump such as a p pump or bosch ape as found on Mack's. I wouldn't overboost regardless of block.
 

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There are many variations of the 7.3L. The idi non- turbo are mostly the same. Then the first di turbo motors used pump- line- nozzle and were similar to the international 444 motors. The blocks were not interchangeable with the previous 7.3. Then in 98/99 they upgraded again with the hoop and piezo injectors making it a quasi common rail system. I think you could interchange blocks with the previous 7.3L but obviously the heads and everything else were totally different. Even the latest 7.3L had changes like the type of injectors used, and the metallurgical change of the connecting rods. As far as what international was doing with their 444... I don't know. I think they mirrored the injection systems but there were front dress changes that made them a little different. As far as reliability goes, obviously properly taken care of and not abused any of them can go 500k without a problem. I've never heard that the industrial motors lasting longer but they were de-rated from their Ford counterparts. I believe the internal parts are the same on all.
 

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The only ones I've had experience with are the IDI non turbo engines. There was an IDI turbo for a short while. The DI engines were the Powerstrokes and those are different animals.
 

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Discussion Starter #6
What was the first year the 7.3 had "electronic junk" on it? or has it always had some? I am looking for an f450 flatbed to use in an RV conversion. I know that there are box trucks that will give me the same utility, but I have never seen a box truck that is 4x4, unless it was a custom conversation. A large number of the flatbeds are 4x4. Some people put 6BT's in these when the 7.3 gives up the ghost but I would like to ride the wave of the 7.3 until it dies. I prefer engines without electronics - I know they don't have quite the same fuel economy but they are cheaper to fix and maintain. I would, however, like to put an allison 2xxx in the truck and some point, which requires electronics :(
 

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What was the first year the 7.3 had "electronic junk" on it? or has it always had some? :(
My understanding: from the first Powerstroke motor, the 7.3s had computer-controlled injection. That was 1994 or 1994.5 or so.

And, all of the IDIs were, basically, mechanical.

Roy
 

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Irhunter, I believe you're correct there. My shop manual shows 3 different 7.3's in 1994. There was an IDI, IDI turbo, and a DI that year. The DI would have been the electronic Power Stroke. In 1995 it only shows the DI engine.
 

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All the IDIs had rotary Stanadyne injection pumps...from the first 6.9 to the turbo 7.3. One of their few, IMHO, weak points. It seems common for guys to need pump rebuilds in the 100 to 150k range. But, no electronics there.

The first Powerstrokes ran electronically-controlled hydraulically-powered unit injectors.

I have never heard of anyone converting the DI motors to run an injection pump.

Roy
 

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Yes, my first 6.9 IDI injection pump died at about 100,000 miles. Just after the warranty ran out. LOL. Was stuck in Bluefield WVA for a few days. The Ford dealer there didn't have a diesel mechanic so I went to the IH truck shop and they fixed it. My 7.3 IDI injection pump lasted 220,000 miles. I think there were some seal issues on the early pumps that they corrected later. The one plus was those pumps are not expensive. The labor cost more than the pump.
 

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My 7.3 IDI injection pump lasted 220,000 miles. I think there were some seal issues on the early pumps that they corrected later. The one plus was those pumps are not expensive. The labor cost more than the pump.
Maybe you are right about the early ones being the source of their bad rap. But, I still think 220k on a Stanadyne is unusual.

You are certainly right...they are not expensive to replace.
 

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Both of my replacement pumps have been done by IH shops. Their parts were a bit cheaper than Ford but the labor a bit more. I figured that since they made the engines they'd sure know what they were doing. There were actually some special Stanadyne pumps made for those engine designed for lighter weight fuel in ultra cold climates. They had better seals and hardened parts.Those pumps were supposed to be vastly superior to the regular line but I have no idea about their part numbers but it's referred to a Stanadyne Arctic pump. The Turtle IV custom F350 had one of those.
 

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Well, that's interesting. Was the normal pump used on the IDIs the same as Chevy used on their 6.2s?
 

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Discussion Starter #15
Thank you! I am taking notes! Will the same transmissions hook up to the earlier engines as well as the later engines? My dream is an Allison 6 speed. I am targeting 1999 to 2002 vehicles because they have air bags (safety feature).
 

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I am not clear on what you want.

A 6-speed Allison transmission, a 1999+ F350?, and a mechanical 7.3?

Or, what?

4x4 or 2wd?

Roy
 

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Discussion Starter #17 (Edited)
I am looking for a flatbed pickup with a diesel engine - an F450 if Ford...Dodge has the equivalent, but not sure of the number. I have always been partial to Ford for trucks...and Cummins for the engines....but would like this truck to have the 6 speed allison tranny...and yes, 4x4. The fords seem to be more plentiful than the Dodges...finally 1999 to 2002, to get the air bags for driver and passenger.
 

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Yes...Ford seems to have sold a lot more of the over-1-ton trucks. Dodge calls them 4500 or 5500. In that class truck, GM seems to be using a medium-duty chassis...they probably have the tranny you want, but bolted to a Duramax.

I suspect the medium-duty Fords with the Cummins come with an Allison. Not sure about 4x4, however. It would sure make your swap easier if you found a donor truck with the correct engine and transmission...drop the whole thing into your F450.

But, if you want a mechanical Diesel and a 6-speed OD Allison with 4x4...that sounds like a lot of advanced piecing-together. Which means a lot of money or a lot of engineering skill.
 

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Discussion Starter #19
But, if you want a mechanical Diesel and a 6-speed OD Allison with 4x4...that sounds like a lot of advanced piecing-together. Which means a lot of money or a lot of engineering skill.
Yes, I am trying to minimize that. That was the reason for my original question. I know I can't have a completely mechanical engine with the Allison...also, for better or worse, I am targeting the 99-02 model years, which means, I think, that they will have the right kind of electronics for the Allison.
 

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You've seen this?


If I was doing it, I would be looking for a donor truck with a motor and transmission I like...drop the whole thing into your F450. Converting the transmission to a married transfer case or going divorced seems easier than matching an engine/transmission which never came bolted together.

Of course, you have to be careful about your differential gearing. I bet many trucks like the F600 which came with smallish Diesels (e.g., 6BT, 360DT) and an auto had 2-speed rears and/or non-OD transmissions.

Roy
 
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